Obama and the Democrats waged a carefully calibrated and orchestrated convention, culminating in an acceptance speech watched by nearly 80,000 packed into a football stadium and a television audience of 38 million. Never before had so many Americans tuned in to a convention.

Meanwhile, John McCain swung for the fences — and connected. The announcement of Alaska Gov. Sarah Palin as his vice presidential choice sucked up all the non-hurricane news coverage. What had begun to look like a second-rate show compared to the one staged in Denver suddenly had some life. It was as though a low-budget reality TV show had suddenly upstaged a slickly produced Hollywood extravaganza. I watched in amazement as John McCain stood in front of a green screen delivering a not-very-inspiring speech … and 39 million Americans watched with me.

In the days following the convention, the McCain/Palin road show has seriously challenged Barack Obama for the “change” brand — in part because it is such a dramatic visual change. A Republican primary that was waged among a gaggle of boring white guys trying to elbow each other away from the conservative base produced a 21st century ticket. A charismatic female governor has energized the party’s base and given McCain room to become the maverick again. And the campaign has done a good job of positioning Palin as one willing to take on the establishment as well.

The Obama campaign, which did a superb job of staying on message all through the primaries, has not reacted well to the Republican offensive. They have chosen to argue Palin is not a reformer. Obama, himself, even stumbled into a “lipstick on a pig” metaphor this week that allowed the McCain team to knock him off message for a full day. Obama cannot win the presidency running against Sarah Palin, and he shouldn’t try. Soon the glow will fade. The Internet is already buzzing with blog postings ranging from her Christian fundamentalism to her willingness to drill in the Arctic National Wildlife Refuge to her wanting to ban books and her refusal to believe human activity causes global warming.

Obama’s job right now is to run against John McCain and George Bush. His mantra should remain the economy, lost jobs, a trillion-dollar war, healthcare, $4 gasoline, global warming and the leadership that has 80 percent of Americans thinking the country is in trouble. That is what must change. Those are the issues Democrats have some credibility on.

This election is still the Democrats’ to lose. If they are not careful, a few smart and surprising moves by John McCain might just cause them to do that. (Although I don’t believe this week’s polls are necessarily where the campaign will be in four weeks.)

Barack Obama needs to take his brand back. He won’t do that by focusing on Gov. Palin. She boosted the ticket because she brought home the base. That just makes independents and Democrats more important in this election. Obama showed he knew how to motivate them in the primary season, and that is what he needs to do again now.

Goddard is a founding partner of political consultants Goddard Claussen. E-mail: ben@gcsa.com